The Cosby Show veteran is due to appear at a pre-trial hearing next week (01Nov16), as he continues to fight allegations he drugged and sexually assaulted former Temple University employee Andrea Constand at his Pennsylvania home in 2004.

He is facing three charges of felony indecent assault, which his representatives have repeatedly denied, while other alleged victims have also come forward with similar decades-old allegations against Cosby, although the statute of limitations has expired in many of their cases.

On Thursday (27Oct16), Cosby's legal team filed a motion in a Pennsylvania court, insisting the actor's ailing eyesight, coupled with a memory which has "substantially declined", means he is unable to positively identify his accusers and is therefore unable to mount a substantial defence.

"How can a 79-year-old blind man defend himself against a claim that he sexually assaulted someone he supposedly met once, half a century ago?" attorneys Brian MCMonagle and Angela Agrusa state in their legal papers, according to CNN.

"The answer is simple: He cannot, and the Commonwealth knows he cannot... Without his eyesight, Mr. Cosby cannot even determine whether has has ever even seen some of his accusers, let alone develop defenses and gather exculpatory evidence. Moreover, Mr. Cosby's memory has substantially declined in the last decade."

His legal representatives reveal the embattled comedian has also registered himself with the Massachusetts Commission for the Blind, and they plan to present proof of his condition at Tuesday's hearing.

MCMonagle and Agrusa have also used the filing to blast prosecutors, insisting they have "chosen to turn this case into a platform for Mr. Cosby's other accusers to air their even staler, long-ago time-barred claims that were never reported to authorities".

Prosecutors have yet to respond to the motion. They previously criticised Cosby's attorneys for trying to use his "fame and fortune" to cover up his allegedly inappropriate behaviour and "hide his true nature".

The case is tentatively set to go to trial on 5 June (17).